[PATCH v3 0/2] linux-user: Introducing functionality for two time64 syscalls

[PATCH v3 0/2] linux-user: Introducing functionality for two time64 syscalls

[Filip Bozuta]

This two patch series introduces functionality for two year
2038 safe syscalls.

The first patch introduces a little correction for already
implemented normal (32-bit) variants of implemented syscalls.

The second patch introduces the implementation of the
syscalls.

Testing method:

    The implementation of the implemented syscalls was tested
    using recently added time64 test in the LTP test suite.

v3:

    -Added an error check before converting back the value
     of 'struct timespec/timespec64' from host to target

Filip Bozuta (2):
  linux-user: Fix 'mq_timedsend()' and 'mq_timedreceive()'
  linux-user: Add support for 'mq_timedsend_time64()' and
    'mq_timedreceive_time64()'

 linux-user/syscall.c | 74 +++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 67 insertions(+), 7 deletions(-)

-- 
2.25.1

[PATCH v3 1/2] linux-user: Fix 'mq_timedsend()' and 'mq_timedreceive()'

[Filip Bozuta]

Implementations of syscalls 'mq_timedsend()' and 'mq_timedreceive()'
in 'syscall.c' use functions 'target_to_host_timespec()' and
'host_to_target_timespec()' to transfer the value of 'struct timespec'
between target and host. However, the implementations don't check whether
this conversion succeeds and thus can cause an unaproppriate error instead
of the 'EFAULT (Bad address)' which is supposed to be set if the conversion
from target to host fails. This was confirmed with the modified LTP
test suite where test cases with a bad adress for 'timespec' were
added. This modified test suite can be found at:
https://github.com/bozutaf/ltp

Without the changes from this patch the bad adress testcase for 'mq_timedsend()'
succeds unexpectedly, while the test returns errno 'ETIMEOUT' for
'mq_timedreceive()':

mq_timedsend01.c:190: FAIL: mq_timedsend() returned 0, expected -1: SUCCESS (0)
mq_timedreceive01.c:178: FAIL: mq_timedreceive() failed unexpectedly,
expected EFAULT: ETIMEDOUT (110)

After the changes from this patch, testcases for both syscalls fail with EFAULT
as expected, which is the same test result that is received with native execution:

mq_timedsend01.c:187: PASS: mq_timedsend() failed expectedly: EFAULT (14)
mq_timedreceive01.c:180: PASS: mq_timedreceive() failed expectedly: EFAULT (14)

(Patch with this new test case will be sent to LTP mailing list soon)

Signed-off-by: Filip Bozuta <Filip.Bozuta@syrmia.com>
---
 linux-user/syscall.c | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 05f03919ff..4ee1de6e65 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -11817,9 +11817,13 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
 
             p = lock_user (VERIFY_READ, arg2, arg3, 1);
             if (arg5 != 0) {
-                target_to_host_timespec(&ts, arg5);
+                if (target_to_host_timespec(&ts, arg5)) {
+                    return -TARGET_EFAULT;
+                }
                 ret = get_errno(safe_mq_timedsend(arg1, p, arg3, arg4, &ts));
-                host_to_target_timespec(arg5, &ts);
+                if (!is_error(ret) && host_to_target_timespec(arg5, &ts)) {
+                    return -TARGET_EFAULT;
+                }
             } else {
                 ret = get_errno(safe_mq_timedsend(arg1, p, arg3, arg4, NULL));
             }
@@ -11836,10 +11840,14 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
 
             p = lock_user (VERIFY_READ, arg2, arg3, 1);
             if (arg5 != 0) {
-                target_to_host_timespec(&ts, arg5);
+                if (target_to_host_timespec(&ts, arg5)) {
+                    return -TARGET_EFAULT;
+                }
                 ret = get_errno(safe_mq_timedreceive(arg1, p, arg3,
                                                      &prio, &ts));
-                host_to_target_timespec(arg5, &ts);
+                if (!is_error(ret) && host_to_target_timespec(arg5, &ts)) {
+                    return -TARGET_EFAULT;
+                }
             } else {
                 ret = get_errno(safe_mq_timedreceive(arg1, p, arg3,
                                                      &prio, NULL));
-- 
2.25.1

[PATCH v3 2/2] linux-user: Add support for 'mq_timedsend_time64()' and 'mq_timedreceive_time64()'

[Filip Bozuta]

This patch implements functionality for following time64 syscalls:

*mq_timedsend_time64()

    This is a year 2038 safe vairant of syscall:

    int mq_timedsend(mqd_t mqdes, const char *msg_ptr,
                     size_t msg_len, unsigned int msg_prio,
                     const struct timespec *abs_timeout)
    --send a message to a message queue--
    man page: https://www.man7.org/linux/man-pages/man2/mq_timedsend.2.html

*mq_timedreceive_time64()

    This is a year 2038 safe variant of syscall:

    ssize_t mq_timedreceive(mqd_t mqdes, char *msg_ptr,
                            size_t msg_len, unsigned int *msg_prio,
                            const struct timespec *abs_timeout)
    --receive a message from a message queue--
    man page: https://man7.org/linux/man-pages/man3/mq_receive.3.html

Implementation notes:

    These syscalls were implemented in similar ways like
    'mq_timedsend()' and 'mq_timedreceive' except that
    functions 'target_to_host_timespec64()' and
    'host_to_target_timespec64()' were used to convert
    values of 'struct timespec' between host and target.

Signed-off-by: Filip Bozuta <Filip.Bozuta@syrmia.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
---
 linux-user/syscall.c | 58 +++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 55 insertions(+), 3 deletions(-)

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 4ee1de6e65..3331ec9fea 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -829,11 +829,13 @@ safe_syscall5(int, msgrcv, int, msgid, void *, msgp, size_t, sz,
 safe_syscall4(int, semtimedop, int, semid, struct sembuf *, tsops,
               unsigned, nsops, const struct timespec *, timeout)
 #endif
-#ifdef TARGET_NR_mq_timedsend
+#if defined(TARGET_NR_mq_timedsend) || \
+    defined(TARGET_NR_mq_timedsend_time64)
 safe_syscall5(int, mq_timedsend, int, mqdes, const char *, msg_ptr,
               size_t, len, unsigned, prio, const struct timespec *, timeout)
 #endif
-#ifdef TARGET_NR_mq_timedreceive
+#if defined(TARGET_NR_mq_timedreceive) || \
+    defined(TARGET_NR_mq_timedreceive_time64)
 safe_syscall5(int, mq_timedreceive, int, mqdes, char *, msg_ptr,
               size_t, len, unsigned *, prio, const struct timespec *, timeout)
 #endif
@@ -1243,7 +1245,9 @@ static inline abi_long target_to_host_timespec(struct timespec *host_ts,
 }
 #endif
 
-#if defined(TARGET_NR_clock_settime64) || defined(TARGET_NR_futex_time64)
+#if defined(TARGET_NR_clock_settime64) || defined(TARGET_NR_futex_time64) || \
+    defined(TARGET_NR_mq_timedsend_time64) || \
+    defined(TARGET_NR_mq_timedreceive_time64)
 static inline abi_long target_to_host_timespec64(struct timespec *host_ts,
                                                  abi_ulong target_addr)
 {
@@ -11831,6 +11835,27 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
         }
         return ret;
 #endif
+#ifdef TARGET_NR_mq_timedsend_time64
+    case TARGET_NR_mq_timedsend_time64:
+        {
+            struct timespec ts;
+
+            p = lock_user(VERIFY_READ, arg2, arg3, 1);
+            if (arg5 != 0) {
+                if (target_to_host_timespec64(&ts, arg5)) {
+                    return -TARGET_EFAULT;
+                }
+                ret = get_errno(safe_mq_timedsend(arg1, p, arg3, arg4, &ts));
+                if (!is_error(ret) && host_to_target_timespec64(arg5, &ts)) {
+                    return -TARGET_EFAULT;
+                }
+            } else {
+                ret = get_errno(safe_mq_timedsend(arg1, p, arg3, arg4, NULL));
+            }
+            unlock_user(p, arg2, arg3);
+        }
+        return ret;
+#endif
 
 #ifdef TARGET_NR_mq_timedreceive
     case TARGET_NR_mq_timedreceive:
@@ -11858,6 +11883,33 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
         }
         return ret;
 #endif
+#ifdef TARGET_NR_mq_timedreceive_time64
+    case TARGET_NR_mq_timedreceive_time64:
+        {
+            struct timespec ts;
+            unsigned int prio;
+
+            p = lock_user(VERIFY_READ, arg2, arg3, 1);
+            if (arg5 != 0) {
+                if (target_to_host_timespec64(&ts, arg5)) {
+                    return -TARGET_EFAULT;
+                }
+                ret = get_errno(safe_mq_timedreceive(arg1, p, arg3,
+                                                     &prio, &ts));
+                if (!is_error(ret) && host_to_target_timespec64(arg5, &ts)) {
+                    return -TARGET_EFAULT;
+                }
+            } else {
+                ret = get_errno(safe_mq_timedreceive(arg1, p, arg3,
+                                                     &prio, NULL));
+            }
+            unlock_user(p, arg2, arg3);
+            if (arg4 != 0) {
+                put_user_u32(prio, arg4);
+            }
+        }
+        return ret;
+#endif
 
     /* Not implemented for now... */
 /*     case TARGET_NR_mq_notify: */
-- 
2.25.1

Re: [PATCH v3 1/2] linux-user: Fix 'mq_timedsend()' and 'mq_timedreceive()'

[Laurent Vivier]

Le 24/08/2020 à 21:37, Filip Bozuta a écrit :
> Implementations of syscalls 'mq_timedsend()' and 'mq_timedreceive()'
> in 'syscall.c' use functions 'target_to_host_timespec()' and
> 'host_to_target_timespec()' to transfer the value of 'struct timespec'
> between target and host. However, the implementations don't check whether
> this conversion succeeds and thus can cause an unaproppriate error instead
> of the 'EFAULT (Bad address)' which is supposed to be set if the conversion
> from target to host fails. This was confirmed with the modified LTP
> test suite where test cases with a bad adress for 'timespec' were
> added. This modified test suite can be found at:
> https://github.com/bozutaf/ltp
> 
> Without the changes from this patch the bad adress testcase for 'mq_timedsend()'
> succeds unexpectedly, while the test returns errno 'ETIMEOUT' for
> 'mq_timedreceive()':
> 
> mq_timedsend01.c:190: FAIL: mq_timedsend() returned 0, expected -1: SUCCESS (0)
> mq_timedreceive01.c:178: FAIL: mq_timedreceive() failed unexpectedly,
> expected EFAULT: ETIMEDOUT (110)
> 
> After the changes from this patch, testcases for both syscalls fail with EFAULT
> as expected, which is the same test result that is received with native execution:
> 
> mq_timedsend01.c:187: PASS: mq_timedsend() failed expectedly: EFAULT (14)
> mq_timedreceive01.c:180: PASS: mq_timedreceive() failed expectedly: EFAULT (14)
> 
> (Patch with this new test case will be sent to LTP mailing list soon)
> 
> Signed-off-by: Filip Bozuta <Filip.Bozuta@syrmia.com>
> ---
>  linux-user/syscall.c | 16 ++++++++++++----
>  1 file changed, 12 insertions(+), 4 deletions(-)
> 
> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index 05f03919ff..4ee1de6e65 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -11817,9 +11817,13 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
>  
>              p = lock_user (VERIFY_READ, arg2, arg3, 1);
>              if (arg5 != 0) {
> -                target_to_host_timespec(&ts, arg5);
> +                if (target_to_host_timespec(&ts, arg5)) {
> +                    return -TARGET_EFAULT;
> +                }
>                  ret = get_errno(safe_mq_timedsend(arg1, p, arg3, arg4, &ts));
> -                host_to_target_timespec(arg5, &ts);
> +                if (!is_error(ret) && host_to_target_timespec(arg5, &ts)) {
> +                    return -TARGET_EFAULT;
> +                }
>              } else {
>                  ret = get_errno(safe_mq_timedsend(arg1, p, arg3, arg4, NULL));
>              }
> @@ -11836,10 +11840,14 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
>  
>              p = lock_user (VERIFY_READ, arg2, arg3, 1);
>              if (arg5 != 0) {
> -                target_to_host_timespec(&ts, arg5);
> +                if (target_to_host_timespec(&ts, arg5)) {
> +                    return -TARGET_EFAULT;
> +                }
>                  ret = get_errno(safe_mq_timedreceive(arg1, p, arg3,
>                                                       &prio, &ts));
> -                host_to_target_timespec(arg5, &ts);
> +                if (!is_error(ret) && host_to_target_timespec(arg5, &ts)) {
> +                    return -TARGET_EFAULT;
> +                }
>              } else {
>                  ret = get_errno(safe_mq_timedreceive(arg1, p, arg3,
>                                                       &prio, NULL));
> 

Reviewed-by: Laurent Vivier <laurent@vivier.eu>

Re: [PATCH v3 1/2] linux-user: Fix 'mq_timedsend()' and 'mq_timedreceive()'

[Laurent Vivier]

Le 24/08/2020 à 21:37, Filip Bozuta a écrit :
> Implementations of syscalls 'mq_timedsend()' and 'mq_timedreceive()'
> in 'syscall.c' use functions 'target_to_host_timespec()' and
> 'host_to_target_timespec()' to transfer the value of 'struct timespec'
> between target and host. However, the implementations don't check whether
> this conversion succeeds and thus can cause an unaproppriate error instead
> of the 'EFAULT (Bad address)' which is supposed to be set if the conversion
> from target to host fails. This was confirmed with the modified LTP
> test suite where test cases with a bad adress for 'timespec' were
> added. This modified test suite can be found at:
> https://github.com/bozutaf/ltp
> 
> Without the changes from this patch the bad adress testcase for 'mq_timedsend()'
> succeds unexpectedly, while the test returns errno 'ETIMEOUT' for
> 'mq_timedreceive()':
> 
> mq_timedsend01.c:190: FAIL: mq_timedsend() returned 0, expected -1: SUCCESS (0)
> mq_timedreceive01.c:178: FAIL: mq_timedreceive() failed unexpectedly,
> expected EFAULT: ETIMEDOUT (110)
> 
> After the changes from this patch, testcases for both syscalls fail with EFAULT
> as expected, which is the same test result that is received with native execution:
> 
> mq_timedsend01.c:187: PASS: mq_timedsend() failed expectedly: EFAULT (14)
> mq_timedreceive01.c:180: PASS: mq_timedreceive() failed expectedly: EFAULT (14)
> 
> (Patch with this new test case will be sent to LTP mailing list soon)
> 
> Signed-off-by: Filip Bozuta <Filip.Bozuta@syrmia.com>
> ---
>  linux-user/syscall.c | 16 ++++++++++++----
>  1 file changed, 12 insertions(+), 4 deletions(-)
> 
> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index 05f03919ff..4ee1de6e65 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -11817,9 +11817,13 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
>  
>              p = lock_user (VERIFY_READ, arg2, arg3, 1);
>              if (arg5 != 0) {
> -                target_to_host_timespec(&ts, arg5);
> +                if (target_to_host_timespec(&ts, arg5)) {
> +                    return -TARGET_EFAULT;
> +                }
>                  ret = get_errno(safe_mq_timedsend(arg1, p, arg3, arg4, &ts));
> -                host_to_target_timespec(arg5, &ts);
> +                if (!is_error(ret) && host_to_target_timespec(arg5, &ts)) {
> +                    return -TARGET_EFAULT;
> +                }
>              } else {
>                  ret = get_errno(safe_mq_timedsend(arg1, p, arg3, arg4, NULL));
>              }
> @@ -11836,10 +11840,14 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
>  
>              p = lock_user (VERIFY_READ, arg2, arg3, 1);
>              if (arg5 != 0) {
> -                target_to_host_timespec(&ts, arg5);
> +                if (target_to_host_timespec(&ts, arg5)) {
> +                    return -TARGET_EFAULT;
> +                }
>                  ret = get_errno(safe_mq_timedreceive(arg1, p, arg3,
>                                                       &prio, &ts));
> -                host_to_target_timespec(arg5, &ts);
> +                if (!is_error(ret) && host_to_target_timespec(arg5, &ts)) {
> +                    return -TARGET_EFAULT;
> +                }
>              } else {
>                  ret = get_errno(safe_mq_timedreceive(arg1, p, arg3,
>                                                       &prio, NULL));
> 

Applied to my linux-user-for-5.2 branch.

Thanks,
Laurent

Re: [PATCH v3 2/2] linux-user: Add support for 'mq_timedsend_time64()' and 'mq_timedreceive_time64()'

[Laurent Vivier]

Le 24/08/2020 à 21:37, Filip Bozuta a écrit :
> This patch implements functionality for following time64 syscalls:
> 
> *mq_timedsend_time64()
> 
>     This is a year 2038 safe vairant of syscall:
> 
>     int mq_timedsend(mqd_t mqdes, const char *msg_ptr,
>                      size_t msg_len, unsigned int msg_prio,
>                      const struct timespec *abs_timeout)
>     --send a message to a message queue--
>     man page: https://www.man7.org/linux/man-pages/man2/mq_timedsend.2.html
> 
> *mq_timedreceive_time64()
> 
>     This is a year 2038 safe variant of syscall:
> 
>     ssize_t mq_timedreceive(mqd_t mqdes, char *msg_ptr,
>                             size_t msg_len, unsigned int *msg_prio,
>                             const struct timespec *abs_timeout)
>     --receive a message from a message queue--
>     man page: https://man7.org/linux/man-pages/man3/mq_receive.3.html
> 
> Implementation notes:
> 
>     These syscalls were implemented in similar ways like
>     'mq_timedsend()' and 'mq_timedreceive' except that
>     functions 'target_to_host_timespec64()' and
>     'host_to_target_timespec64()' were used to convert
>     values of 'struct timespec' between host and target.
> 
> Signed-off-by: Filip Bozuta <Filip.Bozuta@syrmia.com>
> Reviewed-by: Laurent Vivier <laurent@vivier.eu>
> ---
>  linux-user/syscall.c | 58 +++++++++++++++++++++++++++++++++++++++++---
>  1 file changed, 55 insertions(+), 3 deletions(-)
> 
> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index 4ee1de6e65..3331ec9fea 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -829,11 +829,13 @@ safe_syscall5(int, msgrcv, int, msgid, void *, msgp, size_t, sz,
>  safe_syscall4(int, semtimedop, int, semid, struct sembuf *, tsops,
>                unsigned, nsops, const struct timespec *, timeout)
>  #endif
> -#ifdef TARGET_NR_mq_timedsend
> +#if defined(TARGET_NR_mq_timedsend) || \
> +    defined(TARGET_NR_mq_timedsend_time64)
>  safe_syscall5(int, mq_timedsend, int, mqdes, const char *, msg_ptr,
>                size_t, len, unsigned, prio, const struct timespec *, timeout)
>  #endif
> -#ifdef TARGET_NR_mq_timedreceive
> +#if defined(TARGET_NR_mq_timedreceive) || \
> +    defined(TARGET_NR_mq_timedreceive_time64)
>  safe_syscall5(int, mq_timedreceive, int, mqdes, char *, msg_ptr,
>                size_t, len, unsigned *, prio, const struct timespec *, timeout)
>  #endif
> @@ -1243,7 +1245,9 @@ static inline abi_long target_to_host_timespec(struct timespec *host_ts,
>  }
>  #endif
>  
> -#if defined(TARGET_NR_clock_settime64) || defined(TARGET_NR_futex_time64)
> +#if defined(TARGET_NR_clock_settime64) || defined(TARGET_NR_futex_time64) || \
> +    defined(TARGET_NR_mq_timedsend_time64) || \
> +    defined(TARGET_NR_mq_timedreceive_time64)
>  static inline abi_long target_to_host_timespec64(struct timespec *host_ts,
>                                                   abi_ulong target_addr)
>  {
> @@ -11831,6 +11835,27 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
>          }
>          return ret;
>  #endif
> +#ifdef TARGET_NR_mq_timedsend_time64
> +    case TARGET_NR_mq_timedsend_time64:
> +        {
> +            struct timespec ts;
> +
> +            p = lock_user(VERIFY_READ, arg2, arg3, 1);
> +            if (arg5 != 0) {
> +                if (target_to_host_timespec64(&ts, arg5)) {
> +                    return -TARGET_EFAULT;
> +                }
> +                ret = get_errno(safe_mq_timedsend(arg1, p, arg3, arg4, &ts));
> +                if (!is_error(ret) && host_to_target_timespec64(arg5, &ts)) {
> +                    return -TARGET_EFAULT;
> +                }
> +            } else {
> +                ret = get_errno(safe_mq_timedsend(arg1, p, arg3, arg4, NULL));
> +            }
> +            unlock_user(p, arg2, arg3);
> +        }
> +        return ret;
> +#endif
>  
>  #ifdef TARGET_NR_mq_timedreceive
>      case TARGET_NR_mq_timedreceive:
> @@ -11858,6 +11883,33 @@ static abi_long do_syscall1(void *cpu_env, int num, abi_long arg1,
>          }
>          return ret;
>  #endif
> +#ifdef TARGET_NR_mq_timedreceive_time64
> +    case TARGET_NR_mq_timedreceive_time64:
> +        {
> +            struct timespec ts;
> +            unsigned int prio;
> +
> +            p = lock_user(VERIFY_READ, arg2, arg3, 1);
> +            if (arg5 != 0) {
> +                if (target_to_host_timespec64(&ts, arg5)) {
> +                    return -TARGET_EFAULT;
> +                }
> +                ret = get_errno(safe_mq_timedreceive(arg1, p, arg3,
> +                                                     &prio, &ts));
> +                if (!is_error(ret) && host_to_target_timespec64(arg5, &ts)) {
> +                    return -TARGET_EFAULT;
> +                }
> +            } else {
> +                ret = get_errno(safe_mq_timedreceive(arg1, p, arg3,
> +                                                     &prio, NULL));
> +            }
> +            unlock_user(p, arg2, arg3);
> +            if (arg4 != 0) {
> +                put_user_u32(prio, arg4);
> +            }
> +        }
> +        return ret;
> +#endif
>  
>      /* Not implemented for now... */
>  /*     case TARGET_NR_mq_notify: */
> 

Applied to my linux-user-for-5.2 branch.

Thanks,
Laurent